Flexible hose with connect flange and method for obtaining same

ABSTRACT

The invention concerns a flexible hose with connect flange and a method for obtaining such a hose. The flexible hose ( 1 ) whereof the elastomer wall ( 1   a ) is reinforced by at least a main carcass ( 2 ) comprises flexible cables, including at least at one of its ends an annular flange ( 3 ), provided with longitudinal perforations, whereto is fixed at least the main carcass, said flange having an external diameter not greater than the external diameter of the hose wall proximate to the flange. The invention is characterised in that the flange comprises perforations ( 34   a ) emerging on one or more indentation(s) ( 12 ) provided on the outer surface ( 9 ) of the hose wall and whereof the dimensions enable to house therein at least linking means ( 15 ) externally accessible for abutting connection of pipes without interposition of an intermediate component between their respective flanges.

[0001] The present invention relates to a flexible hose with connectingflange and a process for obtaining the same.

[0002] The invention relates more particularly to a flexible hose usedto establish pliable transport lines, serving to load/unload the cargoof oil tankers, from a fixed or relatively mobile installation, or tolink two oil installations, at least one of which is mobile, the mobileinstallations being, for example, installations exposed to the swelland/or the tide.

[0003] In order to facilitate the production, transport and installationthereof, such hoses, the internal diameter of which can exceed 600 mm,are produced in 6 to 15 meter lengths and are provided at their endswith connecting flanges to enable them to be joined to one anotherand/or to an oil installation.

[0004] Such hoses are subjected to various high stresses resultingespecially from the internal pressure of the transported fluid and frommovements and deformations of the line. These hoses must exhibit a rangeof properties, such as resistance to the internal pressure of thedelivery of the fluid, resistance to longitudinal traction, resistanceto crushing, resistance to bending-induced fatigue and to torsionalforces, good flexibility combined with resistance to ovalization toprevent the hose from fracturing when flexed.

[0005] In order to obtain such properties, it is known, especially byvirtue of patent applications 1 480 225 and 2 418 900, to usereinforcement or carcass plies, made of pliable and strong metallic ortextile cords divided into pairs of plies mutually separated by a layerof rubber, as well as “integrated” connecting flanges, constituted by atleast two annular elements nesting partially one inside the other andenclosing between them the radially erect ends of the metallic plies ofat least one carcass. The flanges are positioned at the ends of the tubeprior to the vulcanization of the elastomer wall of the hose, thevulcanization ensuring the integration of the whole. The hose comprisesa main carcass intended to bear the internal pressure of the fluid andin which the plies of each pair are constituted by parallel metalliccords orientated obliquely in opposite directions in the one and theother plies according to angles proximate to the angle of equilibrium. Asecondary carcass constituted by pairs of plies of metallic or textilecords according to angles greater or less than 55° confers the requiredbending properties. In order to supplement and/or replace the secondarycarcass, it is known to utilize metallic reinforcing rings or a helicalarmoring.

[0006] According to a first type of flange revealed in the two aforesaidpatent applications, the flange possesses a diameter greater than thewall of the hose. The prominent annular part of the flange compriseslongitudinal through-bores enabling the hoses to be connected by meansof nuts and bolts. It has been shown that a hose provided with such aflange does not have sufficient resistance for certain applications,especially for connecting the hose to a fixed point. In this case, theflange is actually subjected to high traction and bending forces andruptures of the hose have been discovered at the junction of the hosewith the base of the prominent annular part of the flange. Moreover, forthe installation of a line, it is desirable to be able to wind thejoined-up hoses onto a reel. In order to allow take-up on the reel andto avoid all contact between the flanges and the reel, it is necessaryto provide rubber bosses at the level of the flanges.

[0007] In order to replace this first type of flange, a hose has beenproposed which has a conical or cylindrically conical exterior shape atits ends, in order to confer a variation in regular rigidity, andprovided with a second type of flange, of outer diameter less than thediameter of the hose, a flange of this kind being revealed in patentapplication 2 418 900. Owing to this flange configuration, reinforcementplies can be bent radially inward for the outer plies and outward forthe inner plies at the level of the flange, said flange serving to fixsaid bent plies. Thus, the strength of the hose at the level of theconnection is reinforced. Nevertheless, from its front connecting face,such a flange has longitudinal dummy bores, which require the use of anintermediate component in order to connect the flanges of two successivehoses.

[0008] The object of the present invention is to propose a hose withconnecting flange which is strong and whose connection to another hoseis realized without an intermediate component and such that joined-uphoses can be taken up on a reel.

[0009] This object is achieved by the fact that the flexible hoseaccording to the invention, the elastomer wall of which is reinforced byat least one main carcass containing pliable cords and which comprisesat one at least of its ends an annular connecting flange, provided, fromits transversely external end surface, with longitudinal bores, to whichflange at least the main carcass is fixed, said flange having an outerdiameter less than or equal to the outer diameter of the wall of thehose proximate to the flange, is characterized in that the flangecomprises bores, “emerging” bores, which emerge on one or moreindentations made on the outer surface of the wall of the hose and thedimensions of which allow at least one externally accessible couplingmeans to be housed there, for connecting hoses end to end without anyintermediate component interposed between their respective flanges.

[0010] According to one particularity, each emerging bore emerges on aseparate indentation.

[0011] According to one embodiment, the flange comprises “non-emerging”bores, which do not emerge on an indentation and which are tapped overat least a part thereof for the screwing of a complementary threaded rodof the aforesaid coupling means, the emerging bores being untapped.

[0012] In one particular embodiment, the emerging bores and thenon-emerging bores are alternately and peripherally distributed over theend surface of the flange.

[0013] Advantageously, the non-emerging bores contain a bottomseparating said bores from the wall of the hose and constitute dummybores of the flange.

[0014] Advantageously, at least a part of the walls of the indentationsis lined with a sealing strip by which contact of a carcass with theexterior can be prevented.

[0015] According to one embodiment, the main reinforcement carcass isformed by one or more pairs of concentric plies radially spaced bylayers of elastomer, each pair being constituted by two elastomer pliesand parallel metallic cords orientated obliquely in the oppositedirection in the one and the other ply such as to form angles of 20° to70° relative to the axis of the hose.

[0016] According to one particularity, the hose comprises a secondaryreinforcement carcass of greater diameter than the main carcass andradially spaced toward the outside of the latter by a layer ofelastomer, said secondary carcass comprising concentric plies ofelastomer and of metallic and/or textile cords, joined directly to oneanother and/or spaced by layers of elastomer, the cords of the maincarcass forming angles substantially equal to the angle of equilibrium,while the cords of the secondary carcass form angles between 20° and70°.

[0017] Advantageously, the flange comprises at least two axiallyjoined-together annular elements, a longitudinally external element anda longitudinally internal element, each provided with coaxial holesforming at least a part of the aforesaid bores, at least the internalelement possessing an internal diameter less than or equal to the maincarcass and at least the main carcass being radially bent, the radialpart thus bent being interposed and fixed between the two elements ofthe flange.

[0018] According to one particularity, the hose has, close to theflange, a conical exterior shape, with an increase in thickness in thedirection of the flange, obtained by increasing the thickness of anelastomer layer and/or insertion of an elastomer layer and/or of pliesbetween plies of a carcass.

[0019] Advantageously, the radial bent part of the main carcass extendsradially beyond at least the longitudinally internal element of theflange and is bent longitudinally at a distance from the end of thehose, at least a part of the plies which constitute it being interposedbetween the plies of the secondary carcass so as to fix these latter tothe flange via the plies of the main carcass.

[0020] According to one particularity, the hose comprises, close to theflange, longitudinal-reinforcement plies, comprising cords arrangedsubstantially parallel to the axis of the hose, said plies being joinedto the flange and to the main carcass and/or to the secondary carcass.

[0021] Advantageously, the reinforcement plies have diameters greaterthan that of the plies of the main carcass and less than that of theplies of the secondary carcass and are joined together and joined to themain carcass, at least one of the plies having its double-bent endconnected to at least one ply of the secondary carcass.

[0022] Advantageously, the flange comprises tubular elements inserted atleast partially in the coaxial holes of the longitudinally internal andexternal elements and the external surfaces of which are lined at leastpartially with elastomer to ensure that the leak-tightness of the flangeat the level of said bores and to guarantee that the various elements ofthe flange are strongly joined.

[0023] According to one particularity, the hose comprises metallic ringsor a helical metallic armoring embedded in the layer of elastomercontained between the main carcass and the secondary carcass.

[0024] Another object of the invention is to propose a process forobtaining such a hose.

[0025] This object is achieved by the fact that the process forobtaining a flexible hose according to the invention comprises a stepfor fixing cores against the transversely internal surface of the flangeat the level of at least certain of the longitudinal bores, a step forpositioning and adjusting the flange at the end of the hose, said coresbeing prominent relative to the outer surface of the wall, made of crudenon-vulcanized elastomer, of the hose, or having a surface lyingsubstantially flush with said outer wall surface, and a step forremoving these cores after the elastomer has been vulcanized.

[0026] According to one particularity, the process according to theinvention comprises a step for fitting the sealing strip onto the cores,said strips remaining stuck to the vulcanized elastomer wall of theindentations after the cores are removed.

[0027] The invention will be better understood and other objects,details, characteristics and advantages will appear more clearly in thecourse of the following detailed explanatory description of a currentlypreferred particular embodiment of the invention, with reference to theappended schematic drawing, in which:

[0028]FIG. 1 represents a partial half-view, in axial section, of oneend of a hose according to the invention at the level of a non-emergingbore;

[0029]FIG. 2 represents a partial half-view, in axial section, of oneend of a hose according to the invention at the level of an emergingbore;

[0030]FIG. 3A represents an exploded view, in longitudinal section, ofvarious elements constituting a flange of the hose according to theinvention, at the level of a non-emerging bore;

[0031]FIG. 3B represents a perspective view of a tubular element of aflange of the hose according to the invention;

[0032]FIG. 4A represents a perspective view of two hoses according tothe invention, joined by their connecting flanges;

[0033]FIG. 4B represents an enlarged view of a part of FIG. 4A;

[0034]FIG. 5 represents a partial half-view, in axial section along theplane V-V of FIG. 4A, of two connected hoses;

[0035]FIGS. 6A and 6B respectively represent a perspective view and arear view of the internal element of a connecting flange according tothe invention, illustrating the positioning of molding cores for theprocess for obtaining a hose according to the invention;

[0036]FIGS. 7A and 7B represent, respectively, a perspective view and asectional view of a molding core used in the process for obtaining ahose according to the invention;

[0037]FIG. 8 represents a perspective view of a sealing strip intendedto be placed against the wall of an indentation of the outer surface ofthe hose.

[0038] With reference to FIGS. 1 and 2, the hose 1 comprises a wall 1 a,which is substantially cylindrical along a main axis X and is made ofelastomer, such as vulcanized rubber or a similar pliable material, andwhich is reinforced by a main carcass 2 formed by at least two pairs 21,22 of coaxial plies. In the remainder of the description, the term“rubber” refers to any type of elastomer suitable for constituting thevarious layers of the wall 1 a, the nature of the rubber being able, ina known manner, to be different from one layer to the other. The pliesof each pair 21, 22 are applied substantially one against the other andare constituted by parallel metallic cords embedded in a film of rubber,the cords being orientated obliquely in opposite directions in one andthe other plies of a pair. The pairs 21, 22 are radially spaced apart bya layer of rubber 3. The pair 21 of plies of lesser diameter isinternally lined by an inner layer of rubber 4 forming the internalsurface 5 of the hose.

[0039] The wall 1 a of the hose is reinforced by a secondary carcass 6,which is radially spaced relative to the main carcass by a layer ofrubber 7, said secondary carcass comprising concentric plies 61-65constituted by metallic or textile cords embedded in a film of rubber.The plies are applied directly one to the other and/or are radiallyspaced by layers of rubber. The ply 61 of greater diameter is externallylined by an external layer 8 of rubber forming the external surface 9 ofthe hose. In the exemplary embodiment illustrated, the secondary carcass6 comprises a first set of two plies 64, 65 applied directly one uponthe other and comprising, for example, metallic cords. This first set isspaced radially inward by a layer of rubber 10 of a second set of threeplies 61-63 of larger diameters, each constituted, for example, bytextile cords embedded in a film of rubber. These three latter plies61-63 applied directly one against the other are spaced apart by layersof rubber 601, 602 close to the flange, such as is described below.

[0040] The twilled cords of the plies of the main 2 and secondary 6carcass can form an angle of between 20° and 70° relative to the axis Xof the hose. The twilled cords of the pairs 21, 22 of the main carcasspreferably form an angle close to the angle of equilibrium, i.e. 55°.The main carcass 2 is thus mainly intended to bear the internal pressureof the conveyed fluid. The traction forces are borne both by the maincarcass 2 and by the secondary carcass 6. The angles of the cords of theplies 61-65 of the secondary carcass are adjusted as a function of theproperties sought. In order to increase the resistance of the hose totraction forces, the angle of these cords is reduced relative to theangle of equilibrium. The angle of these cords can also be increased toenhance the flexibility of the hose. The hose can further comprise rigidrings 11 or a helical armoring of constant or variable pitch, disposedin the elastomer layer 7 contained between the main carcass 2 and thesecondary carcass 6. These rings 11 serve to support the carcasses whenthese are subjected to tensile stress and also allow improvement to thecrushing resistance of the hose.

[0041] The hose comprises, at one at least of its ends, a connectingflange 3, to which at least the main carcass 2 is fixed. With referenceto FIG. 3A, the flange comprises two partially nestable annularelements, a longitudinally external element 31, comprising an externalsurface 310, constituting the transversely external end surface of theflange, and an internal clamping surface 311 and a longitudinallyinternal element 32, comprising a clamping surface 321, an internalsurface 320 constituting the transversely internal surface of theflange. Said elements, hereinafter referred to as the external element31 and the internal element 32, comprise concentrically distributedlongitudinal through-holes 313, 323. When the two elements are partiallynested, with their clamping surfaces 311, 321 facing each other, theholes of the elements are arranged coaxially to form flange-connectingbores 34 a, 34 b. The external element 31 has an external diameter andan internal diameter smaller, respectively, than the external andinternal diameters of the wall 1 a of the hose. The internal element 32has internal and external diameters smaller than those of the externalelement 31 and the external element comprises on its internal clampingsurface 311 an annular groove 312, in which the internal element nests.According to one particular embodiment, connecting sockets 33 arepartially fitted in the holes 313, 323 of the elements in order tofacilitate the assembly of the flange, to ensure a strong fasteningbetween the two elements and to prevent the infiltration of waterthrough said holes. The two pairs 21, 22 of the main carcass are bentradially outward, the bent parts 21 a, 22 a thus formed are applied oneagainst the other, without an intermediate rubber layer, and areinterposed and fixed between the annular elements 31, 32 of the flange,distorting the connecting sockets 33.

[0042] By way of example, the holes 313 of the external element 31 havea first part 313 a extended by a second part 313 b of smaller diameter,emerging on the outer surface 310 of the element, a shoulder 314 beingformed which is orientated in the same direction as the internal surfaceof the element. The holes 323 of the internal element 32 have a firstpart 323 a emerging on the clamping surface 321, of diameter equal tothe first part 313 a of the external element, and is extended by asecond part 323 b, a shoulder 324 being formed which is orientated inthe same direction as the clamping surface. The connecting sockets 33have an internal diameter substantially equal to that of the second part323 b of the holes of the internal element and an outer diametersubstantially equal to that of the first parts 313 a, 323 a. The outersurface of the connecting sockets contains at the ends circularindentations 331, 332 extending as far as the circular edges 333, 334 ofthe connecting sockets and forming oblique shoulders 336, 337. Theexternal diameter of the connecting sockets at the level of at least oneof the indentations is less than or equal to the diameter of the secondpart 313 b of the external element. In order to carry out the assemblyof the flange, the connecting sockets are lined with raw rubber, theninserted by force into the external and internal elements until thecircular edges 333 of the connecting sockets are substantially in thesame plane as the external surface 310 of the external element, the bentparts 21 a, 22 a being enclosed between the two elements. In thisassembly, the rubber spreads to fill the spaces at the level of theshoulders facing the elements and the connecting sockets and to formsealing joints 17 a-17 d after vulcanization. A clearance e (FIG. 2) ismaintained between the circular edge 334 of the connecting sockets andthe shoulders 324 of the internal elements to allow adjustment to theclamping of the two elements. In order to facilitate the distribution ofthe raw rubber and to ensure a strong joining of the two elements, theconnecting sockets have longitudinal peripheral flutes 335, as can beseen in FIG. 3B.

[0043] Advantageously, the outer surface 9 of the hose has a conicalshape at the level of the flange (over a length ranging from 0.5 to 4meters, with a growing thickness in the direction of the flange. Theconicity is obtained by progressive increase in the layer of rubber 10between the two sets of plies of the secondary carcass and by thepresence of layers of rubber 601, 602 between the plies 61-63 of thesecond set. The diameter of the plies 61-63 of the second setprogressively increases approaching the flange 3 so as to arrive at adiameter greater than that of the internal element 32 of the flange,said plies stopping before the external element 31 of the flange. Thefirst set of plies 64, 65 extends, for its part, into the conical partof the wall with a substantially constant diameter.

[0044] Advantageously, the secondary carcass 6 is also fixed to theflange by at least a part of its plies. The bent parts 21 a, 22 a of themain carcass, interposed between the annular elements of the flange, arebent longitudinally rearward, the longitudinal bent parts 21 b, 22 bthus formed are interposed between plies of the second set of thesecondary carcass, and/or fixed against the latter, over a lengthranging, for example, from 300 to 400 mm. By way of example, thelongitudinal bent part 22 b of the pair of lesser diameter is appliedagainst the internal surface of the ply 63 of lesser diameter of thesecond set and the longitudinal bent part 21 b of the other pairinterposes itself between the aforesaid ply 62 and the following ply 63.

[0045] The hose further contains longitudinal reinforcements 19 at thelevel of the flange. These longitudinal reinforcements are formed, forexample, by three concentric, longitudinal-reinforcement plies, an upperply 19 a, an intermediate ply 19 b and a lower ply 19 c, of diametergreater than the main carcass and less than the secondary carcass. Eachply is formed, for example, by textile cords, arranged in asubstantially axial manner and embedded in a film of rubber. These threeplies are disposed one against the other and joined together by thelower ply 19 c with the main carcass and bent with the latter so as tobe interposed between the two elements 31, 32 of the flange. Preferably,the reinforcement plies 19 a-19 c extend as far as the bores of theflanges and stop substantially at the level of the external circularsurface 325 of the internal element. The upper ply 19 a extends radiallyoutward in an oblique manner and interposes itself between the two plies64, 65 of the secondary carcass, which extend obliquely inward. Thus, inthe present embodiment, the plies of the first set of the secondarycarcass are fixed indirectly to the flange, via the longitudinalreinforcements and the main carcass. In constructional variants, somelongitudinal-reinforcement plies are joined, on the one hand, to theflange and, on the other hand, between and/or against plies of the mainand/or secondary carcass, in which case plies can have diameters greaterthan those of the plies of the secondary carcass or less than those ofthe plies of the main carcass.

[0046] According to the invention, the external surface 9 of the hosecontains indentations 12 or openings on which bores 34 a or the whole ofthe bores of the flange emerge. In the example described, theindentations 12 are arranged such that one bore in two is emerging. FIG.1 represents a longitudinal section of a hose according to the inventionat the level of a non-emerging bore 34 b and FIG. 2 represents alongitudinal section of a same hose at the level of an emerging bore 34a. In the case of a hose of 600 mm internal diameter, comprising aflange provided with 20 bores (according to standard ANSI B. 16.5—Class150), the hose according to the invention will have 10 emerging boresand 10 non-emerging bores distributed alternately.

[0047] The non-emerging bores 34 b have a tapped part, whilst theemerging bores are smooth over the whole of their length.Advantageously, the tapped part of the non-emerging bores is constitutedby the second part 323 b of the bores of the internal element of theflange, such as represented in FIG. 3A. The non-emerging bores 34 b areobturated by metallic plates 13 welded onto the internal surface 322 ofthe internal element in order to prevent any infiltration of water intothe hose. Of course, a preformed internal element, having emerging holesand dummy holes, can be envisaged.

[0048] This connecting flange allows hoses to be joined end to end orthe hose to be joined to a fixed or mobile installation without the needfor an intermediate component. FIGS. 4A, 4B and 5 illustrate theconnection of two hoses according to the invention. The connection oftwo hoses 101, 102 is effected by arranging the non-emerging bores 34 bof the hoses to face the emerging bores 34 a, as follows. Threaded rods14 are screwed into the non-emerging bores 34 b of the flanges of eachhose and the two hoses are then positioned in such a way to allow theprominent portions of threaded rods of one hose to be inserted into theemerging bores of the other hose. Nuts 15 are then screwed onto the endsof the threaded rods positioned in the indentations 12. According to thesize of the indentations, the nuts can be positioned in the indentationsprior to the complete insertion of the threaded rods into saidindentations. The nuts are then screwed manually or mechanically.Preferably, the indentations do not extend beyond the internal circularsurface of the internal element of the flange and represent a volumesubstantially corresponding to the correct volume necessary to allow thenuts to be clamped on the threaded rods.

[0049] Advantageously, the external 9 and internal 4 layers of the hoseextend beyond the reinforcement carcasses 2, 6 and take up residence inrecesses 315, 316 made in the outer surface 310 of the external elementof the flange, to form an integrated connecting joint of the hose. Theexternal element contains on its outer surface 310 a first circularrecess 315 extending as far as the external circular wall 317, in whichthe external layer 8 of the hoses take up residence. Similarly, theouter surface 310 contains a second recess 316 extending as far as theinternal circular wall 318 of the element, in which the internal layer 4of the wall takes up residence. The internal and external layers housedin the recesses form an axial excess thickness, visible in FIG. 2,serving as a sealing joint 18 a, 18 b for the connection of the twohoses.

[0050] Advantageously, the upper part of the vertical rubber walls 121of the indentations 12 is lined with a metallic strip 16 over a heightcorresponding to the various plies present at this level of the wall ofthe hose, namely the plies 61-63 of the second set of the secondarycarcass and the longitudinally bent parts 21 b, 22 b of the pairs of themain carcass. These plies, which lie flush with the vertical walls 121of the indentations, are thus protected from the exterior. The strip 16,which has been fixed to the wall of the indentation duringvulcanization, rests upon a shoulder 121 a present on the rubber wallsof the indentation, as well as on the internal element of the flange.The upper edge of the sealing strip can come to lie flush with theexternal surface 9 of the wall of the hose or can be spaced from thelatter by a height substantially equal to or less than the thickness ofthe external layer 8.

[0051] The hoses according to the invention, provided at each of theirends with a flange combined with indentations, as previously described,can be connected end to end to constitute a transport line between anoil tanker and a fixed or mobile point, or between two oilinstallations. For the laying of such lines, the end-to-end hoses canadvantageously be wound around a reel. Of course, the ends of the linemust be linked to a complementary flange on the tanker or the fixed ormobile point. The line obtained has good strength properties, includingat the level of its connection to a fixed point. The hose according tothe invention can be used to realize lines of great length. By way ofexample, in the case of recent drillings of deep-sea oil deposits,referred to as deep “offshore” deposits, at depths sometimes reaching1000 meters or more, the various drilling wells are linked by flexiblehoses to a single oil platform on which the crude oil is pre-processed.The platform is then linked by a transport line to an intermediatestorage tanker, which must be positioned outside the zone of thedrilling wells and at a safe distance from the platform, which has beenfixed at about 1.6 km. A transport line of this length, in particular atthe level of its ends, suffers stresses greater than those encounteredin traditional lines, previously mentioned, of a maximum length of 300meters at a depth of about 100 meters. The current solution consists inrealizing a line with rigid stainless steel hoses, at a depth of theorder of 600 meters. In order to replace a rigid line of this kind oflimited diameter and the installation of which is complex and laborious,the hose according to the invention can be used to realize a strongline, easily laid from a reel, said line being able, for example, to bejoined to submerged buoys at a depth of 300 meters.

[0052] The hose according to the invention can also be used incombination with another flange of the prior art to produce flexiblelines, in which case the hose has at one end a flange combined withindentations and at its other end a flange of the prior art such asthose described in the aforesaid patent applications.

[0053] The hose according to the invention, provided with indentationsproximate to the flange to form emerging bores, can be obtained by thefollowing process. With reference to FIGS. 6A, 6B, 7A and 7B, prior tothe installation of the flange preceding the curing or vulcanization ofthe hose, molding cores 17 are fitted against the internal surface 322of the internal element of the flange, via bores of the flange which arerequired to be made emerging once the hose is realized. In the exemplaryembodiment, ten cores 17 are joined to obtain access to one bore in two.It should be noted that, in FIGS. 6A and 6B, the bores 34 b which appearbetween two cores and which will not be emerging are not obturated. Itis also feasible to fix a sealing strip prior to the installation of thecores.

[0054] Each core 17 has in cross section a substantially trapezoidalshape, the large base 171 of which is orientated radially outward whenthe core 17 is joined on the flange. One of the small sidesperpendicular to the bases 171, 172 of the trapezoidal core forms thesurface of the core intended to make contact with the flange. Thiscontact surface 173 possesses a tapped bore 173 c, into which a holdingbolt inserted through a smooth bore 34 a of the flange can be screwed.In the case of a flange such as previously described, the two elements31, 32 of the flange are pre-joined by means of the connecting sockets33, maintaining a space between the elements in order subsequently toallow the positioning of the plies, and the cores are then fittedagainst the internal surface of the internal element. The holding boltsof the cores can in this case also ensure the clamping of the annularelements of the flange in the axial direction during vulcanization. Itshould be noted that FIGS. 6A and 6B only illustrate the positioning ofthe cores relative to the internal element of the flange, the cores notbeing fixed on said element.

[0055] The contact surface 173 further has a shoulder 173 a, the shapeof which is adapted to the radius of curvature of the flange and to therounded junction between the external circular wall 325 and the internalsurface 322 of the internal element. This shoulder 173 a allows precisepositioning of the cores on the flange. This shoulder defines an upperedge 173 b which links said contact surface 173 to the upper surface171. When the core is joined on the flange, this upper edge 173 b isprominent relative to the external circular wall 325 of the internalelement. The upper surface 171 of the core preferably has a convexshape, the radius of curvature of which substantially corresponds tothat of the outer surface 9 of the hose. This upper surface comes to liesubstantially flush with the outer surface of the hose when the flangeis installed on the hose. Preferably, the small base 172 of the core isnot prominent relative to the internal circular surface 326. In order toform an indentation 12, the volume of which substantially corresponds tothe volume necessary to allow fixing of the hose and thus maintain amaximum quantity of rubber at the level of the flange, the core has anoverall conical shape in the longitudinal direction, the rear surface177, opposite to the contact surface 173, being smaller in size than thelatter. Moreover, the oblique surfaces 178, 179 of the trapezoidal coreare linked to the upper surface 171 by flat surfaces 178 a, 178 bsubstantially perpendicular to the small base 172. As illustrated solelyin FIGS. 7A and 7B, the small base can have a concave outer shape,possibly forming a continuous surface with the aforesaid oblique walls.

[0056] Advantageously, the positioning of the sealing strips 16 isrealized by means of the cores 17. The sealing strips have acircumference corresponding to the aforesaid flat parts 178 a, 178 b, tothe upper edge 173 b and to the rear surface 177 of the cores and arejoined on the cores against these portions.

[0057] With reference to FIG. 8, the sealing strip 16 preferably has thegeneral shape of a U, the base 164 and the arms of which are intended tocome respectively against the upper edge 173 b and the flat parts 178 a,178 b. The free ends 162,163 of the arms are curved toward each otherand are intended to come against the rear surface 177 of the core.

[0058] This configuration lends an elasticity to the sealing strip whichfacilitates its installation on the core, but has the drawback of notlining a part of the wall of the indentation. The metallic plies will beable to be adjusted such that they do not come between the two free endsof the stirrup, the plies will be separated at this level of the wall ofthe indentation by a thickness of rubber. To ensure the verticalpositioning of the strip 16, the flat parts are linked to the upper edge173 b of the contact surface by chamfers 174, said chamfers notextending as far as the upper surface 171 in order to form stops 175,against which the strip rests by its upper edge 161. Moreover, the rearsurface has a shoulder 177 a serving as a stop for the strip. When thecore is joined on the flange, the sealing strip is in contact with theexternal circular surface 325 of the internal element by the lower edge165 of its base 164, which has a radius of curvature corresponding tothat of the flange. In this embodiment, the upper edge 161 of the stripwill be disposed at a distance from the external surface 9 at leastequal to the height of the aforesaid stops. In the embodimentillustrated in FIG. 8, the arms 168, 167 linking the base 164 to thefree ends 162, 163 have a height which decreases from the free ends tothe base. Of course, a strip of constant height is also feasible, byproviding notches 169 on the lower edge 165 at the level of the junctionof the arms to the base, as illustrated in FIG. 2.

[0059] Following adjustment and positioning of the reinforcement pliesrelative to the two elements of the flange, to the connecting socketsand to the cores, as well as the ones relative to the others, the wholeis joined together by vulcanization in the traditional manner. In orderto avoid additional cuts, some raw rubber, in the form of film, forexample, can be previously arranged between the cores 17 prior to theflange being fitted onto the wall of the hose. The holding bolts of thecores are then unscrewed and the cores withdrawn, leaving in theindentations thus formed the sealing strips which have stuck to thewalls of the indentations during vulcanization. In order to facilitatethe extraction of the cores, tapped bores 171 a can be provided on theupper surfaces 171 of the cores. The cores can thus be extracted bypulling on a tool screwed in said bores. Moreover, the cores can bepreviously lined with an anti-adhesive to prevent them from attaching tothe rubber during vulcanization.

[0060] Although the invention has been described in connection with aparticular embodiment, it is obvious that it is in no way limitedthereto and that it comprises all the technical equivalents of the meansdescribed, as well as combinations thereof provided they fall within thescope of the invention. By way of example, the distribution of theemerging and non-emerging bores can vary. Moreover, it can be envisagedto provide only emerging bores, accessible by separate indentations orby a single annular indentation.

1. A flexible hose (1), the elastomer wall (1 a) of which is reinforcedby at least one main carcass (2) containing pliable cords and whichcomprises at one at least of its ends an annular connecting flange (3),provided, from its transversely external end surface, with longitudinalbores, to which flange at least the main carcass is fixed, said flangehaving an outer diameter less than or equal to the outer diameter of thewall of the hose proximate to the flange, which hose is characterized inthat the flange comprises bores (34 a), “emerging” bores, which emergeon one or more indentations (12) made on the outer surface (9) of thewall of the hose and the dimensions of which allow at least oneexternally accessible coupling means (15) to be housed there, forconnecting hoses end to end without any intermediate componentinterposed between their respective flanges.
 2. The hose as claimed inclaim 1, characterized in that each emerging bore (34 a) emerges on aseparate indentation (12).
 3. The hose as claimed in claim 1 or 2,characterized in that the flange comprises “non-emerging” bores (34 b),which do not emerge on an indentation and which are tapped over at leasta part thereof for the screwing of a complementary threaded rod (14) ofthe aforesaid coupling means (15), the emerging bores (34 a) beinguntapped.
 4. The hose as claimed in claim 3, characterized in that theemerging bores (34 a) and the non-emerging bores (34 b) are alternatelyand peripherally distributed over the external end surface (310) of theflange.
 5. The hose as claimed in claim 4, characterized in that thenon-emerging bores (34 b) contain a bottom separating said bores fromthe wall of the hose and constitute dummy bores of the flange.
 6. Thehose as claimed in one of claims 1 to 5, characterized in that at leasta part of the walls (121) of the indentations (12) is lined with asealing strip (16) by which contact of a carcass (2, 6) with theexterior can be prevented.
 7. The hose as claimed in one of claims 1 to6, characterized in that the main reinforcement carcass (2) is formed byone or more pairs (21, 22) of concentric plies radially spaced by layersof elastomer (3), each pair being constituted by two elastomer plies andparallel metallic cords orientated obliquely in the opposite directionin the one and the other ply such as to form angles of 20° to 70°relative to the axis (X) of the hose.
 8. The hose as claimed in claim 7,characterized in that it comprises a secondary reinforcement carcass (6)of greater diameter than the main carcass (2) and radially spaced towardthe outside of the latter by a layer of elastomer (7), said secondarycarcass comprising concentric plies (61-67) of elastomer and of metallicand/or textile cords, joined directly to one another and/or spaced bylayers of elastomer (10), the cords of the main carcass forming anglessubstantially equal to the angle of equilibrium, while the cords of thesecondary carcass form angles between 20° and 70°.
 9. The hose asclaimed in claim 8, characterized in that the flange (2) comprises atleast two axially joined annular elements, a longitudinally externalelement (31) and a longitudinally internal element (32), each providedwith coaxial holes forming at least a part of the aforesaid bores (34 a,34 b), at least the internal element possessing an internal diameterless than or equal to the main carcass (2) and at least the main carcassbeing radially bent, the radial part (21 a, 22 a) thus bent beinginterposed and fixed between the two elements of the flange.
 10. Thehose as claimed in claim 9, characterized in that it has, close to theflange (2), a conical exterior shape, with an increase in thickness inthe direction of the flange, obtained by increasing the thickness of anelastomer layer and/or insertion of an elastomer layer and/or of pliesbetween plies of a carcass.
 11. The hose as claimed in claim 9 or 10,characterized in that the radial bent part (21 a, 22 a) of the maincarcass extends radially beyond at least the longitudinally internalelement (32) of the flange and is bent longitudinally at a distance fromthe end of the hose, at least a part of the plies which constitute itbeing interposed between the plies of the secondary carcass so as to fixthese latter to the flange via the plies of the main carcass.
 12. Thehose as claimed in one of claims 9 to 11, characterized in that itcomprises, close to the flange (3), longitudinal-reinforcement plies(19), comprising cords arranged substantially parallel to the axis (X)of the hose, said plies being joined to the flange and to the maincarcass (2) and/or to the secondary carcass (6).
 13. The hose as claimedin claim 12, characterized in that the reinforcement plies havediameters greater than that of the plies of the main carcass (2) andless than that of the plies of the secondary carcass (6) and are joinedtogether and joined to the main carcass, at least one of the plies (19c) having its double-bent end connected to at least one ply (64, 65) ofthe secondary carcass.
 14. The hose as claimed in one of claims 9 to 13,characterized in that the flange comprises tubular elements (33)inserted at least partially in coaxial holes of the longitudinallyinternal and external elements (31, 32) and the external surfaces (330)of which are lined at least partially with elastomer to ensure theleak-tightness of the flange at the level of said bores and to guaranteethat the various elements of the flange are strongly joined.
 15. Thehose as claimed in one of claims 9 to 14, characterized in that itcomprises metallic rings (11) or a helical metallic armoring embedded inthe layer of elastomer (7) contained between the main carcass (2) andthe secondary carcass (6).
 16. A process for obtaining a flexible hoseaccording to one of the preceding claims, characterized in that itcomprises a step for fixing cores (17) against the transversely internalsurface (322) of the flange (3) at the level of at least certain of thelongitudinal bores, a step for positioning and adjusting the flange atthe end of the hose, said cores being prominent relative to the outersurface of the wall, made of crude non-vulcanized elastomer, of thehose, or having a surface lying substantially flush with said outer wallsurface, and a step for removing these cores after the elastomer hasbeen vulcanized.
 17. The process as claimed in claim 156 [sic],characterized in that it comprises a step for fitting the sealing strip(16) onto the cores (17), said strips remaining stuck to the vulcanizedelastomer wall of the indentations (12) after the cores are removed.